Windows Security Centre or McAfee Security Centre (post-SP2)

After SP2 upgrade, MSC (McAfee Security Centre) popped up and advised that
WSC (Windows Security Centre) be disabled so as not to conflict with MSC.
Makes sense to run only one of them. All the info from McAfee makes it clear
that (in their opinion) MSC is better than WSC. Is it? I mean, they're
biased in favour of their own product. I would suppose that MS would say the
opposite.

MSC only runs McAfee AV and I have no interest in purchasing the other
software they keep advising me to get (Firewall, Antispam, Privacy), not
when these things are available for free/lower cost. WSC includes AV and
Personal Firewall. Is the MS AV or PF any good?

At the moment I've left things as they were -- McAfee for Anti-Virus,
Windows for Firewall and Automatic Updates -- but I'd like to settle on one
only and be done with it. Any opinions?
Thanks.